gdb/ui-file.c

   1 /* UI_FILE - a generic STDIO like output stream.
   2
   3    Copyright (C) 1999, 2000, 2001, 2002, 2007, 2008, 2009, 2010, 2011
   4    Free Software Foundation, Inc.
   5
   6    This file is part of GDB.
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  20
  21 /* Implement the ``struct ui_file'' object.  */
  22
  23 #include "defs.h"
  24 #include "ui-file.h"
  25 #include "gdb_obstack.h"
  26 #include "gdb_string.h"
  27 #include "gdb_select.h"
  28
  29 #include <errno.h>
  30
  31 static ui_file_isatty_ftype null_file_isatty;
  32 static ui_file_write_ftype null_file_write;
  33 static ui_file_write_ftype null_file_write_async_safe;
  34 static ui_file_fputs_ftype null_file_fputs;
  35 static ui_file_read_ftype null_file_read;
  36 static ui_file_flush_ftype null_file_flush;
  37 static ui_file_delete_ftype null_file_delete;
  38 static ui_file_rewind_ftype null_file_rewind;
  39 static ui_file_put_ftype null_file_put;
  40
  41 struct ui_file
  42   {
  43     int *magic;
  44     ui_file_flush_ftype *to_flush;
  45     ui_file_write_ftype *to_write;
  46     ui_file_write_async_safe_ftype *to_write_async_safe;
  47     ui_file_fputs_ftype *to_fputs;
  48     ui_file_read_ftype *to_read;
  49     ui_file_delete_ftype *to_delete;
  50     ui_file_isatty_ftype *to_isatty;
  51     ui_file_rewind_ftype *to_rewind;
  52     ui_file_put_ftype *to_put;
  53     void *to_data;
  54   };
  55 int ui_file_magic;
  56
  57 struct ui_file *
  58 ui_file_new (void)
  59 {
  60   struct ui_file *file = xmalloc (sizeof (struct ui_file));
  61
  62   file->magic = &ui_file_magic;
  63   set_ui_file_data (file, NULL, null_file_delete);
  64   set_ui_file_flush (file, null_file_flush);
  65   set_ui_file_write (file, null_file_write);
  66   set_ui_file_write_async_safe (file, null_file_write_async_safe);
  67   set_ui_file_fputs (file, null_file_fputs);
  68   set_ui_file_read (file, null_file_read);
  69   set_ui_file_isatty (file, null_file_isatty);
  70   set_ui_file_rewind (file, null_file_rewind);
  71   set_ui_file_put (file, null_file_put);
  72   return file;
  73 }
  74
  75 void
  76 ui_file_delete (struct ui_file *file)
  77 {
  78   file->to_delete (file);
  79   xfree (file);
  80 }
  81
  82 static int
  83 null_file_isatty (struct ui_file *file)
  84 {
  85   return 0;
  86 }
  87
  88 static void
  89 null_file_rewind (struct ui_file *file)
  90 {
  91   return;
  92 }
  93
  94 static void
  95 null_file_put (struct ui_file *file,
  96                ui_file_put_method_ftype *write,
  97                void *dest)
  98 {
  99   return;
 100 }
 101
 102 static void
 103 null_file_flush (struct ui_file *file)
 104 {
 105   return;
 106 }
 107
 108 static void
 109 null_file_write (struct ui_file *file,
 110                  const char *buf,
 111                  long sizeof_buf)
 112 {
 113   if (file->to_fputs == null_file_fputs)
 114     /* Both the write and fputs methods are null.  Discard the
 115        request.  */
 116     return;
 117   else
 118     {
 119       /* The fputs method isn't null, slowly pass the write request
 120          onto that.  FYI, this isn't as bad as it may look - the
 121          current (as of 1999-11-07) printf_* function calls fputc and
 122          fputc does exactly the below.  By having a write function it
 123          is possible to clean up that code.  */
 124       int i;
 125       char b[2];
 126
 127       b[1] = '\0';
 128       for (i = 0; i < sizeof_buf; i++)
 129         {
 130           b[0] = buf[i];
 131           file->to_fputs (b, file);
 132         }
 133       return;
 134     }
 135 }
 136
 137 static long
 138 null_file_read (struct ui_file *file,
 139                 char *buf,
 140                 long sizeof_buf)
 141 {
 142   errno = EBADF;
 143   return 0;
 144 }
 145
 146 static void
 147 null_file_fputs (const char *buf, struct ui_file *file)
 148 {
 149   if (file->to_write == null_file_write)
 150     /* Both the write and fputs methods are null.  Discard the
 151        request.  */
 152     return;
 153   else
 154     {
 155       /* The write method was implemented, use that.  */
 156       file->to_write (file, buf, strlen (buf));
 157     }
 158 }
 159
 160 static void
 161 null_file_write_async_safe (struct ui_file *file,
 162                             const char *buf,
 163                             long sizeof_buf)
 164 {
 165   return;
 166 }
 167
 168 static void
 169 null_file_delete (struct ui_file *file)
 170 {
 171   return;
 172 }
 173
 174 void *
 175 ui_file_data (struct ui_file *file)
 176 {
 177   if (file->magic != &ui_file_magic)
 178     internal_error (__FILE__, __LINE__,
 179                     _("ui_file_data: bad magic number"));
 180   return file->to_data;
 181 }
 182
 183 void
 184 gdb_flush (struct ui_file *file)
 185 {
 186   file->to_flush (file);
 187 }
 188
 189 int
 190 ui_file_isatty (struct ui_file *file)
 191 {
 192   return file->to_isatty (file);
 193 }
 194
 195 void
 196 ui_file_rewind (struct ui_file *file)
 197 {
 198   file->to_rewind (file);
 199 }
 200
 201 void
 202 ui_file_put (struct ui_file *file,
 203               ui_file_put_method_ftype *write,
 204               void *dest)
 205 {
 206   file->to_put (file, write, dest);
 207 }
 208
 209 void
 210 ui_file_write (struct ui_file *file,
 211                 const char *buf,
 212                 long length_buf)
 213 {
 214   file->to_write (file, buf, length_buf);
 215 }
 216
 217 void
 218 ui_file_write_async_safe (struct ui_file *file,
 219                           const char *buf,
 220                           long length_buf)
 221 {
 222   file->to_write_async_safe (file, buf, length_buf);
 223 }
 224
 225 long
 226 ui_file_read (struct ui_file *file, char *buf, long length_buf)
 227 {
 228   return file->to_read (file, buf, length_buf);
 229 }
 230
 231 void
 232 fputs_unfiltered (const char *buf, struct ui_file *file)
 233 {
 234   file->to_fputs (buf, file);
 235 }
 236
 237 void
 238 set_ui_file_flush (struct ui_file *file, ui_file_flush_ftype *flush)
 239 {
 240   file->to_flush = flush;
 241 }
 242
 243 void
 244 set_ui_file_isatty (struct ui_file *file, ui_file_isatty_ftype *isatty)
 245 {
 246   file->to_isatty = isatty;
 247 }
 248
 249 void
 250 set_ui_file_rewind (struct ui_file *file, ui_file_rewind_ftype *rewind)
 251 {
 252   file->to_rewind = rewind;
 253 }
 254
 255 void
 256 set_ui_file_put (struct ui_file *file, ui_file_put_ftype *put)
 257 {
 258   file->to_put = put;
 259 }
 260
 261 void
 262 set_ui_file_write (struct ui_file *file,
 263                     ui_file_write_ftype *write)
 264 {
 265   file->to_write = write;
 266 }
 267
 268 void
 269 set_ui_file_write_async_safe (struct ui_file *file,
 270                               ui_file_write_async_safe_ftype *write_async_safe)
 271 {
 272   file->to_write_async_safe = write_async_safe;
 273 }
 274
 275 void
 276 set_ui_file_read (struct ui_file *file, ui_file_read_ftype *read)
 277 {
 278   file->to_read = read;
 279 }
 280
 281 void
 282 set_ui_file_fputs (struct ui_file *file, ui_file_fputs_ftype *fputs)
 283 {
 284   file->to_fputs = fputs;
 285 }
 286
 287 void
 288 set_ui_file_data (struct ui_file *file, void *data,
 289                   ui_file_delete_ftype *delete)
 290 {
 291   file->to_data = data;
 292   file->to_delete = delete;
 293 }
 294
 295 /* ui_file utility function for converting a ``struct ui_file'' into
 296    a memory buffer.  */
 297
 298 struct accumulated_ui_file
 299 {
 300   char *buffer;
 301   long length;
 302 };
 303
 304 static void
 305 do_ui_file_xstrdup (void *context, const char *buffer, long length)
 306 {
 307   struct accumulated_ui_file *acc = context;
 308
 309   if (acc->buffer == NULL)
 310     acc->buffer = xmalloc (length + 1);
 311   else
 312     acc->buffer = xrealloc (acc->buffer, acc->length + length + 1);
 313   memcpy (acc->buffer + acc->length, buffer, length);
 314   acc->length += length;
 315   acc->buffer[acc->length] = '\0';
 316 }
 317
 318 char *
 319 ui_file_xstrdup (struct ui_file *file, long *length)
 320 {
 321   struct accumulated_ui_file acc;
 322
 323   acc.buffer = NULL;
 324   acc.length = 0;
 325   ui_file_put (file, do_ui_file_xstrdup, &acc);
 326   if (acc.buffer == NULL)
 327     acc.buffer = xstrdup ("");
 328   if (length != NULL)
 329     *length = acc.length;
 330   return acc.buffer;
 331 }
 332
 333 static void
 334 do_ui_file_obsavestring (void *context, const char *buffer, long length)
 335 {
 336   struct obstack *obstack = (struct obstack *) context;
 337
 338   obstack_grow (obstack, buffer, length);
 339 }
 340
 341 char *
 342 ui_file_obsavestring (struct ui_file *file, struct obstack *obstack,
 343                       long *length)
 344 {
 345   ui_file_put (file, do_ui_file_obsavestring, obstack);
 346   *length = obstack_object_size (obstack);
 347   obstack_1grow (obstack, '\0');
 348   return obstack_finish (obstack);
 349 }
 350 \f
 351 /* A pure memory based ``struct ui_file'' that can be used an output
 352    buffer.  The buffers accumulated contents are available via
 353    ui_file_put().  */
 354
 355 struct mem_file
 356   {
 357     int *magic;
 358     char *buffer;
 359     int sizeof_buffer;
 360     int length_buffer;
 361   };
 362
 363 static ui_file_rewind_ftype mem_file_rewind;
 364 static ui_file_put_ftype mem_file_put;
 365 static ui_file_write_ftype mem_file_write;
 366 static ui_file_delete_ftype mem_file_delete;
 367 static struct ui_file *mem_file_new (void);
 368 static int mem_file_magic;
 369
 370 static struct ui_file *
 371 mem_file_new (void)
 372 {
 373   struct mem_file *stream = XMALLOC (struct mem_file);
 374   struct ui_file *file = ui_file_new ();
 375
 376   set_ui_file_data (file, stream, mem_file_delete);
 377   set_ui_file_rewind (file, mem_file_rewind);
 378   set_ui_file_put (file, mem_file_put);
 379   set_ui_file_write (file, mem_file_write);
 380   stream->magic = &mem_file_magic;
 381   stream->buffer = NULL;
 382   stream->sizeof_buffer = 0;
 383   stream->length_buffer = 0;
 384   return file;
 385 }
 386
 387 static void
 388 mem_file_delete (struct ui_file *file)
 389 {
 390   struct mem_file *stream = ui_file_data (file);
 391
 392   if (stream->magic != &mem_file_magic)
 393     internal_error (__FILE__, __LINE__,
 394                     _("mem_file_delete: bad magic number"));
 395   if (stream->buffer != NULL)
 396     xfree (stream->buffer);
 397   xfree (stream);
 398 }
 399
 400 struct ui_file *
 401 mem_fileopen (void)
 402 {
 403   return mem_file_new ();
 404 }
 405
 406 static void
 407 mem_file_rewind (struct ui_file *file)
 408 {
 409   struct mem_file *stream = ui_file_data (file);
 410
 411   if (stream->magic != &mem_file_magic)
 412     internal_error (__FILE__, __LINE__,
 413                     _("mem_file_rewind: bad magic number"));
 414   stream->length_buffer = 0;
 415 }
 416
 417 static void
 418 mem_file_put (struct ui_file *file,
 419               ui_file_put_method_ftype *write,
 420               void *dest)
 421 {
 422   struct mem_file *stream = ui_file_data (file);
 423
 424   if (stream->magic != &mem_file_magic)
 425     internal_error (__FILE__, __LINE__,
 426                     _("mem_file_put: bad magic number"));
 427   if (stream->length_buffer > 0)
 428     write (dest, stream->buffer, stream->length_buffer);
 429 }
 430
 431 void
 432 mem_file_write (struct ui_file *file,
 433                 const char *buffer,
 434                 long length_buffer)
 435 {
 436   struct mem_file *stream = ui_file_data (file);
 437
 438   if (stream->magic != &mem_file_magic)
 439     internal_error (__FILE__, __LINE__,
 440                     _("mem_file_write: bad magic number"));
 441   if (stream->buffer == NULL)
 442     {
 443       stream->length_buffer = length_buffer;
 444       stream->sizeof_buffer = length_buffer;
 445       stream->buffer = xmalloc (stream->sizeof_buffer);
 446       memcpy (stream->buffer, buffer, length_buffer);
 447     }
 448   else
 449     {
 450       int new_length = stream->length_buffer + length_buffer;
 451
 452       if (new_length >= stream->sizeof_buffer)
 453         {
 454           stream->sizeof_buffer = new_length;
 455           stream->buffer = xrealloc (stream->buffer, stream->sizeof_buffer);
 456         }
 457       memcpy (stream->buffer + stream->length_buffer, buffer, length_buffer);
 458       stream->length_buffer = new_length;
 459     }
 460 }
 461 \f
 462 /* ``struct ui_file'' implementation that maps directly onto
 463    <stdio.h>'s FILE.  */
 464
 465 static ui_file_write_ftype stdio_file_write;
 466 static ui_file_write_async_safe_ftype stdio_file_write_async_safe;
 467 static ui_file_fputs_ftype stdio_file_fputs;
 468 static ui_file_read_ftype stdio_file_read;
 469 static ui_file_isatty_ftype stdio_file_isatty;
 470 static ui_file_delete_ftype stdio_file_delete;
 471 static struct ui_file *stdio_file_new (FILE *file, int close_p);
 472 static ui_file_flush_ftype stdio_file_flush;
 473
 474 static int stdio_file_magic;
 475
 476 struct stdio_file
 477   {
 478     int *magic;
 479     FILE *file;
 480     /* The associated file descriptor is extracted ahead of time for
 481        stdio_file_write_async_safe's benefit, in case fileno isn't async-safe.  */
 482     int fd;
 483     int close_p;
 484   };
 485
 486 static struct ui_file *
 487 stdio_file_new (FILE *file, int close_p)
 488 {
 489   struct ui_file *ui_file = ui_file_new ();
 490   struct stdio_file *stdio = xmalloc (sizeof (struct stdio_file));
 491
 492   stdio->magic = &stdio_file_magic;
 493   stdio->file = file;
 494   stdio->fd = fileno (file);
 495   stdio->close_p = close_p;
 496   set_ui_file_data (ui_file, stdio, stdio_file_delete);
 497   set_ui_file_flush (ui_file, stdio_file_flush);
 498   set_ui_file_write (ui_file, stdio_file_write);
 499   set_ui_file_write_async_safe (ui_file, stdio_file_write_async_safe);
 500   set_ui_file_fputs (ui_file, stdio_file_fputs);
 501   set_ui_file_read (ui_file, stdio_file_read);
 502   set_ui_file_isatty (ui_file, stdio_file_isatty);
 503   return ui_file;
 504 }
 505
 506 static void
 507 stdio_file_delete (struct ui_file *file)
 508 {
 509   struct stdio_file *stdio = ui_file_data (file);
 510
 511   if (stdio->magic != &stdio_file_magic)
 512     internal_error (__FILE__, __LINE__,
 513                     _("stdio_file_delete: bad magic number"));
 514   if (stdio->close_p)
 515     {
 516       fclose (stdio->file);
 517     }
 518   xfree (stdio);
 519 }
 520
 521 static void
 522 stdio_file_flush (struct ui_file *file)
 523 {
 524   struct stdio_file *stdio = ui_file_data (file);
 525
 526   if (stdio->magic != &stdio_file_magic)
 527     internal_error (__FILE__, __LINE__,
 528                     _("stdio_file_flush: bad magic number"));
 529   fflush (stdio->file);
 530 }
 531
 532 static long
 533 stdio_file_read (struct ui_file *file, char *buf, long length_buf)
 534 {
 535   struct stdio_file *stdio = ui_file_data (file);
 536
 537   if (stdio->magic != &stdio_file_magic)
 538     internal_error (__FILE__, __LINE__,
 539                     _("stdio_file_read: bad magic number"));
 540
 541   /* For the benefit of Windows, call gdb_select before reading from
 542      the file.  Wait until at least one byte of data is available.
 543      Control-C can interrupt gdb_select, but not read.  */
 544   {
 545     fd_set readfds;
 546     FD_ZERO (&readfds);
 547     FD_SET (stdio->fd, &readfds);
 548     if (gdb_select (stdio->fd + 1, &readfds, NULL, NULL, NULL) == -1)
 549       return -1;
 550   }
 551
 552   return read (stdio->fd, buf, length_buf);
 553 }
 554
 555 static void
 556 stdio_file_write (struct ui_file *file, const char *buf, long length_buf)
 557 {
 558   struct stdio_file *stdio = ui_file_data (file);
 559
 560   if (stdio->magic != &stdio_file_magic)
 561     internal_error (__FILE__, __LINE__,
 562                     _("stdio_file_write: bad magic number"));
 563   /* Calling error crashes when we are called from the exception framework.  */
 564   if (fwrite (buf, length_buf, 1, stdio->file))
 565     ;
 566 }
 567
 568 static void
 569 stdio_file_write_async_safe (struct ui_file *file,
 570                              const char *buf, long length_buf)
 571 {
 572   struct stdio_file *stdio = ui_file_data (file);
 573
 574   if (stdio->magic != &stdio_file_magic)
 575     {
 576       /* gettext isn't necessarily async safe, so we can't use _("error message") here.
 577          We could extract the correct translation ahead of time, but this is an extremely
 578          rare event, and one of the other stdio_file_* routines will presumably catch
 579          the problem anyway.  For now keep it simple and ignore the error here.  */
 580       return;
 581     }
 582
 583   /* This is written the way it is to avoid a warning from gcc about not using the
 584      result of write (since it can be declared with attribute warn_unused_result).
 585      Alas casting to void doesn't work for this.  */
 586   if (write (stdio->fd, buf, length_buf))
 587     ;
 588 }
 589
 590 static void
 591 stdio_file_fputs (const char *linebuffer, struct ui_file *file)
 592 {
 593   struct stdio_file *stdio = ui_file_data (file);
 594
 595   if (stdio->magic != &stdio_file_magic)
 596     internal_error (__FILE__, __LINE__,
 597                     _("stdio_file_fputs: bad magic number"));
 598   /* Calling error crashes when we are called from the exception framework.  */
 599   if (fputs (linebuffer, stdio->file))
 600     ;
 601 }
 602
 603 static int
 604 stdio_file_isatty (struct ui_file *file)
 605 {
 606   struct stdio_file *stdio = ui_file_data (file);
 607
 608   if (stdio->magic != &stdio_file_magic)
 609     internal_error (__FILE__, __LINE__,
 610                     _("stdio_file_isatty: bad magic number"));
 611   return (isatty (stdio->fd));
 612 }
 613
 614 /* Like fdopen().  Create a ui_file from a previously opened FILE.  */
 615
 616 struct ui_file *
 617 stdio_fileopen (FILE *file)
 618 {
 619   return stdio_file_new (file, 0);
 620 }
 621
 622 struct ui_file *
 623 gdb_fopen (char *name, char *mode)
 624 {
 625   FILE *f = fopen (name, mode);
 626
 627   if (f == NULL)
 628     return NULL;
 629   return stdio_file_new (f, 1);
 630 }
 631
 632 /* ``struct ui_file'' implementation that maps onto two ui-file objects.  */
 633
 634 static ui_file_write_ftype tee_file_write;
 635 static ui_file_fputs_ftype tee_file_fputs;
 636 static ui_file_isatty_ftype tee_file_isatty;
 637 static ui_file_delete_ftype tee_file_delete;
 638 static ui_file_flush_ftype tee_file_flush;
 639
 640 static int tee_file_magic;
 641
 642 struct tee_file
 643   {
 644     int *magic;
 645     struct ui_file *one, *two;
 646     int close_one, close_two;
 647   };
 648
 649 struct ui_file *
 650 tee_file_new (struct ui_file *one, int close_one,
 651               struct ui_file *two, int close_two)
 652 {
 653   struct ui_file *ui_file = ui_file_new ();
 654   struct tee_file *tee = xmalloc (sizeof (struct tee_file));
 655
 656   tee->magic = &tee_file_magic;
 657   tee->one = one;
 658   tee->two = two;
 659   tee->close_one = close_one;
 660   tee->close_two = close_two;
 661   set_ui_file_data (ui_file, tee, tee_file_delete);
 662   set_ui_file_flush (ui_file, tee_file_flush);
 663   set_ui_file_write (ui_file, tee_file_write);
 664   set_ui_file_fputs (ui_file, tee_file_fputs);
 665   set_ui_file_isatty (ui_file, tee_file_isatty);
 666   return ui_file;
 667 }
 668
 669 static void
 670 tee_file_delete (struct ui_file *file)
 671 {
 672   struct tee_file *tee = ui_file_data (file);
 673
 674   if (tee->magic != &tee_file_magic)
 675     internal_error (__FILE__, __LINE__,
 676                     _("tee_file_delete: bad magic number"));
 677   if (tee->close_one)
 678     ui_file_delete (tee->one);
 679   if (tee->close_two)
 680     ui_file_delete (tee->two);
 681
 682   xfree (tee);
 683 }
 684
 685 static void
 686 tee_file_flush (struct ui_file *file)
 687 {
 688   struct tee_file *tee = ui_file_data (file);
 689
 690   if (tee->magic != &tee_file_magic)
 691     internal_error (__FILE__, __LINE__,
 692                     _("tee_file_flush: bad magic number"));
 693   tee->one->to_flush (tee->one);
 694   tee->two->to_flush (tee->two);
 695 }
 696
 697 static void
 698 tee_file_write (struct ui_file *file, const char *buf, long length_buf)
 699 {
 700   struct tee_file *tee = ui_file_data (file);
 701
 702   if (tee->magic != &tee_file_magic)
 703     internal_error (__FILE__, __LINE__,
 704                     _("tee_file_write: bad magic number"));
 705   ui_file_write (tee->one, buf, length_buf);
 706   ui_file_write (tee->two, buf, length_buf);
 707 }
 708
 709 static void
 710 tee_file_fputs (const char *linebuffer, struct ui_file *file)
 711 {
 712   struct tee_file *tee = ui_file_data (file);
 713
 714   if (tee->magic != &tee_file_magic)
 715     internal_error (__FILE__, __LINE__,
 716                     _("tee_file_fputs: bad magic number"));
 717   tee->one->to_fputs (linebuffer, tee->one);
 718   tee->two->to_fputs (linebuffer, tee->two);
 719 }
 720
 721 static int
 722 tee_file_isatty (struct ui_file *file)
 723 {
 724   struct tee_file *tee = ui_file_data (file);
 725
 726   if (tee->magic != &tee_file_magic)
 727     internal_error (__FILE__, __LINE__,
 728                     _("tee_file_isatty: bad magic number"));
 729
 730   return ui_file_isatty (tee->one);
 731 }